Reflfit and Reflpol

Reflfit and its polarized neutron sister reflpol are two of our
reflectometery analysis program. They let you fit your reduced
reflectivity data to a layer model.

You can directly manipulate the layer profile by dragging the
depths and control points around the graph.

You can encode arbitrary constraints among the parameters.

You can fit to any of the layer parameters using a
Levenburg-Marquardt non-linear fitting algorithm. You can also
fit to artificial parameters which encode the constraints, such
as the total depth of a set of equally thick layers.